I have a 4x4 with a little over 1000 miles, should i change the diff fluids for break in?

 

It certainly wouldn't hurt, but I don't think it would hurt to wait a bit either. As a minimum, have you pulled the plugs and looked at the magnets and levels?

I do know guys who religously change out their diff fluids at the 1000 mile mark - trucks and cars.

Its not making any noises is it? In any event, if it'll put your mind at ease to change it, go ahead - it can't hurt.

 

I changed mine at 1000 miles and then again at 13,000. The magnetic plug had a lot more "fuzz" on it at 1000 miles. At 13,000 it had almost none and the oil still looked pretty clean. Can't hurt.

 

I was just thinking the other day, a rare event I know...

On pickuptruck.com there was talk about how GM's axle supplier suggested changing the fluid very soon after your first towing trip...first 500mi of towing or something like that. GM didn't suggest it, but their supplier did.

What occurred to me is that Dodge and GM now share the same supplier, no?

And reading the GM forum there is all this talk of suggestions to only tow in 50mi chunks as the new diff gets hot and needs time to cool. Then change the oil at 500mi... I know they didn't "see the light" and go with the Cummins, but maybe there is something to be learned about the AA&M setups we both now run.

 

I did my first diff fluid change at about 7k and wish I would have done it earlier. It looked pretty nasty and the there was quite a bit of sludge on the magnet. I went to the trouble of jacking up each side of the axle and letting it drain for an hour or so (while I did other honey-dos). I then took a small spatula and scraped out the bottom of the case. Now at 10k, the magnet is looking pretty clean.